1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Garmin GPS driver
4 *
5 * Copyright (C) 2006-2011 Hermann Kneissel herkne@gmx.de
6 *
7 * The latest version of the driver can be found at
8 * http://sourceforge.net/projects/garmin-gps/
9 *
10 * This driver has been derived from v2.1 of the visor driver.
11 */
12
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/timer.h>
17 #include <linux/tty.h>
18 #include <linux/tty_driver.h>
19 #include <linux/tty_flip.h>
20 #include <linux/module.h>
21 #include <linux/spinlock.h>
22 #include <linux/uaccess.h>
23 #include <linux/atomic.h>
24 #include <linux/usb.h>
25 #include <linux/usb/serial.h>
26
27 /* the mode to be set when the port ist opened */
28 static int initial_mode = 1;
29
30 #define GARMIN_VENDOR_ID 0x091E
31
32 /*
33 * Version Information
34 */
35
36 #define VERSION_MAJOR 0
37 #define VERSION_MINOR 36
38
39 #define _STR(s) #s
40 #define _DRIVER_VERSION(a, b) "v" _STR(a) "." _STR(b)
41 #define DRIVER_VERSION _DRIVER_VERSION(VERSION_MAJOR, VERSION_MINOR)
42 #define DRIVER_AUTHOR "hermann kneissel"
43 #define DRIVER_DESC "garmin gps driver"
44
45 /* error codes returned by the driver */
46 #define EINVPKT 1000 /* invalid packet structure */
47
48
49 /* size of the header of a packet using the usb protocol */
50 #define GARMIN_PKTHDR_LENGTH 12
51
52 /* max. possible size of a packet using the serial protocol */
53 #define MAX_SERIAL_PKT_SIZ (3 + 255 + 3)
54
55 /* max. possible size of a packet with worst case stuffing */
56 #define MAX_SERIAL_PKT_SIZ_STUFFED (MAX_SERIAL_PKT_SIZ + 256)
57
58 /* size of a buffer able to hold a complete (no stuffing) packet
59 * (the document protocol does not contain packets with a larger
60 * size, but in theory a packet may be 64k+12 bytes - if in
61 * later protocol versions larger packet sizes occur, this value
62 * should be increased accordingly, so the input buffer is always
63 * large enough the store a complete packet inclusive header) */
64 #define GPS_IN_BUFSIZ (GARMIN_PKTHDR_LENGTH+MAX_SERIAL_PKT_SIZ)
65
66 /* size of a buffer able to hold a complete (incl. stuffing) packet */
67 #define GPS_OUT_BUFSIZ (GARMIN_PKTHDR_LENGTH+MAX_SERIAL_PKT_SIZ_STUFFED)
68
69 /* where to place the packet id of a serial packet, so we can
70 * prepend the usb-packet header without the need to move the
71 * packets data */
72 #define GSP_INITIAL_OFFSET (GARMIN_PKTHDR_LENGTH-2)
73
74 /* max. size of incoming private packets (header+1 param) */
75 #define PRIVPKTSIZ (GARMIN_PKTHDR_LENGTH+4)
76
77 #define GARMIN_LAYERID_TRANSPORT 0
78 #define GARMIN_LAYERID_APPL 20
79 /* our own layer-id to use for some control mechanisms */
80 #define GARMIN_LAYERID_PRIVATE 0x01106E4B
81
82 #define GARMIN_PKTID_PVT_DATA 51
83 #define GARMIN_PKTID_L001_COMMAND_DATA 10
84
85 #define CMND_ABORT_TRANSFER 0
86
87 /* packet ids used in private layer */
88 #define PRIV_PKTID_SET_DEBUG 1
89 #define PRIV_PKTID_SET_MODE 2
90 #define PRIV_PKTID_INFO_REQ 3
91 #define PRIV_PKTID_INFO_RESP 4
92 #define PRIV_PKTID_RESET_REQ 5
93 #define PRIV_PKTID_SET_DEF_MODE 6
94
95
96 #define ETX 0x03
97 #define DLE 0x10
98 #define ACK 0x06
99 #define NAK 0x15
100
101 /* structure used to queue incoming packets */
102 struct garmin_packet {
103 struct list_head list;
104 int seq;
105 /* the real size of the data array, always > 0 */
106 int size;
107 __u8 data[];
108 };
109
110 /* structure used to keep the current state of the driver */
111 struct garmin_data {
112 __u8 state;
113 __u16 flags;
114 __u8 mode;
115 __u8 count;
116 __u8 pkt_id;
117 __u32 serial_num;
118 struct timer_list timer;
119 struct usb_serial_port *port;
120 int seq_counter;
121 int insize;
122 int outsize;
123 __u8 inbuffer [GPS_IN_BUFSIZ]; /* tty -> usb */
124 __u8 outbuffer[GPS_OUT_BUFSIZ]; /* usb -> tty */
125 __u8 privpkt[4*6];
126 spinlock_t lock;
127 struct list_head pktlist;
128 struct usb_anchor write_urbs;
129 };
130
131
132 #define STATE_NEW 0
133 #define STATE_INITIAL_DELAY 1
134 #define STATE_TIMEOUT 2
135 #define STATE_SESSION_REQ1 3
136 #define STATE_SESSION_REQ2 4
137 #define STATE_ACTIVE 5
138
139 #define STATE_RESET 8
140 #define STATE_DISCONNECTED 9
141 #define STATE_WAIT_TTY_ACK 10
142 #define STATE_GSP_WAIT_DATA 11
143
144 #define MODE_NATIVE 0
145 #define MODE_GARMIN_SERIAL 1
146
147 /* Flags used in garmin_data.flags: */
148 #define FLAGS_SESSION_REPLY_MASK 0x00C0
149 #define FLAGS_SESSION_REPLY1_SEEN 0x0080
150 #define FLAGS_SESSION_REPLY2_SEEN 0x0040
151 #define FLAGS_BULK_IN_ACTIVE 0x0020
152 #define FLAGS_BULK_IN_RESTART 0x0010
153 #define FLAGS_THROTTLED 0x0008
154 #define APP_REQ_SEEN 0x0004
155 #define APP_RESP_SEEN 0x0002
156 #define CLEAR_HALT_REQUIRED 0x0001
157
158 #define FLAGS_QUEUING 0x0100
159 #define FLAGS_DROP_DATA 0x0800
160
161 #define FLAGS_GSP_SKIP 0x1000
162 #define FLAGS_GSP_DLESEEN 0x2000
163
164
165
166
167
168
169 /* function prototypes */
170 static int gsp_next_packet(struct garmin_data *garmin_data_p);
171 static int garmin_write_bulk(struct usb_serial_port *port,
172 const unsigned char *buf, int count,
173 int dismiss_ack);
174
175 /* some special packets to be send or received */
176 static unsigned char const GARMIN_START_SESSION_REQ[]
177 = { 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0 };
178 static unsigned char const GARMIN_START_SESSION_REPLY[]
179 = { 0, 0, 0, 0, 6, 0, 0, 0, 4, 0, 0, 0 };
180 static unsigned char const GARMIN_BULK_IN_AVAIL_REPLY[]
181 = { 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0 };
182 static unsigned char const GARMIN_STOP_TRANSFER_REQ[]
183 = { 20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 0, 0 };
184 static unsigned char const GARMIN_STOP_TRANSFER_REQ_V2[]
185 = { 20, 0, 0, 0, 10, 0, 0, 0, 1, 0, 0, 0, 0 };
186
187 /* packets currently unused, left as documentation */
188 #if 0
189 static unsigned char const GARMIN_APP_LAYER_REPLY[]
190 = { 0x14, 0, 0, 0 };
191 static unsigned char const GARMIN_START_PVT_REQ[]
192 = { 20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 49, 0 };
193 static unsigned char const GARMIN_STOP_PVT_REQ[]
194 = { 20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 50, 0 };
195 static unsigned char const PRIVATE_REQ[]
196 = { 0x4B, 0x6E, 0x10, 0x01, 0xFF, 0, 0, 0, 0xFF, 0, 0, 0 };
197 #endif
198
199
200 static const struct usb_device_id id_table[] = {
201 /* the same device id seems to be used by all
202 usb enabled GPS devices */
203 { USB_DEVICE(GARMIN_VENDOR_ID, 3) },
204 { } /* Terminating entry */
205 };
206 MODULE_DEVICE_TABLE(usb, id_table);
207
208
getLayerId(const __u8 *usbPacket)209 static inline int getLayerId(const __u8 *usbPacket)
210 {
211 return __le32_to_cpup((__le32 *)(usbPacket));
212 }
213
getPacketId(const __u8 *usbPacket)214 static inline int getPacketId(const __u8 *usbPacket)
215 {
216 return __le32_to_cpup((__le32 *)(usbPacket+4));
217 }
218
getDataLength(const __u8 *usbPacket)219 static inline int getDataLength(const __u8 *usbPacket)
220 {
221 return __le32_to_cpup((__le32 *)(usbPacket+8));
222 }
223
224
225 /*
226 * check if the usb-packet in buf contains an abort-transfer command.
227 * (if yes, all queued data will be dropped)
228 */
isAbortTrfCmnd(const unsigned char *buf)229 static inline int isAbortTrfCmnd(const unsigned char *buf)
230 {
231 if (memcmp(buf, GARMIN_STOP_TRANSFER_REQ,
232 sizeof(GARMIN_STOP_TRANSFER_REQ)) == 0 ||
233 memcmp(buf, GARMIN_STOP_TRANSFER_REQ_V2,
234 sizeof(GARMIN_STOP_TRANSFER_REQ_V2)) == 0)
235 return 1;
236 else
237 return 0;
238 }
239
240
241
send_to_tty(struct usb_serial_port *port, char *data, unsigned int actual_length)242 static void send_to_tty(struct usb_serial_port *port,
243 char *data, unsigned int actual_length)
244 {
245 if (actual_length) {
246 usb_serial_debug_data(&port->dev, __func__, actual_length, data);
247 tty_insert_flip_string(&port->port, data, actual_length);
248 tty_flip_buffer_push(&port->port);
249 }
250 }
251
252
253 /******************************************************************************
254 * packet queue handling
255 ******************************************************************************/
256
257 /*
258 * queue a received (usb-)packet for later processing
259 */
pkt_add(struct garmin_data *garmin_data_p, unsigned char *data, unsigned int data_length)260 static int pkt_add(struct garmin_data *garmin_data_p,
261 unsigned char *data, unsigned int data_length)
262 {
263 int state = 0;
264 int result = 0;
265 unsigned long flags;
266 struct garmin_packet *pkt;
267
268 /* process only packets containing data ... */
269 if (data_length) {
270 pkt = kmalloc(struct_size(pkt, data, data_length), GFP_ATOMIC);
271 if (!pkt)
272 return 0;
273
274 pkt->size = data_length;
275 memcpy(pkt->data, data, data_length);
276
277 spin_lock_irqsave(&garmin_data_p->lock, flags);
278 garmin_data_p->flags |= FLAGS_QUEUING;
279 result = list_empty(&garmin_data_p->pktlist);
280 pkt->seq = garmin_data_p->seq_counter++;
281 list_add_tail(&pkt->list, &garmin_data_p->pktlist);
282 state = garmin_data_p->state;
283 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
284
285 dev_dbg(&garmin_data_p->port->dev,
286 "%s - added: pkt: %d - %d bytes\n", __func__,
287 pkt->seq, data_length);
288
289 /* in serial mode, if someone is waiting for data from
290 the device, convert and send the next packet to tty. */
291 if (result && (state == STATE_GSP_WAIT_DATA))
292 gsp_next_packet(garmin_data_p);
293 }
294 return result;
295 }
296
297
298 /* get the next pending packet */
pkt_pop(struct garmin_data *garmin_data_p)299 static struct garmin_packet *pkt_pop(struct garmin_data *garmin_data_p)
300 {
301 unsigned long flags;
302 struct garmin_packet *result = NULL;
303
304 spin_lock_irqsave(&garmin_data_p->lock, flags);
305 if (!list_empty(&garmin_data_p->pktlist)) {
306 result = (struct garmin_packet *)garmin_data_p->pktlist.next;
307 list_del(&result->list);
308 }
309 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
310 return result;
311 }
312
313
314 /* free up all queued data */
pkt_clear(struct garmin_data *garmin_data_p)315 static void pkt_clear(struct garmin_data *garmin_data_p)
316 {
317 unsigned long flags;
318 struct garmin_packet *result = NULL;
319
320 spin_lock_irqsave(&garmin_data_p->lock, flags);
321 while (!list_empty(&garmin_data_p->pktlist)) {
322 result = (struct garmin_packet *)garmin_data_p->pktlist.next;
323 list_del(&result->list);
324 kfree(result);
325 }
326 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
327 }
328
329
330 /******************************************************************************
331 * garmin serial protocol handling handling
332 ******************************************************************************/
333
334 /* send an ack packet back to the tty */
gsp_send_ack(struct garmin_data *garmin_data_p, __u8 pkt_id)335 static int gsp_send_ack(struct garmin_data *garmin_data_p, __u8 pkt_id)
336 {
337 __u8 pkt[10];
338 __u8 cksum = 0;
339 __u8 *ptr = pkt;
340 unsigned l = 0;
341
342 dev_dbg(&garmin_data_p->port->dev, "%s - pkt-id: 0x%X.\n", __func__,
343 pkt_id);
344
345 *ptr++ = DLE;
346 *ptr++ = ACK;
347 cksum += ACK;
348
349 *ptr++ = 2;
350 cksum += 2;
351
352 *ptr++ = pkt_id;
353 cksum += pkt_id;
354
355 if (pkt_id == DLE)
356 *ptr++ = DLE;
357
358 *ptr++ = 0;
359 *ptr++ = (-cksum) & 0xFF;
360 *ptr++ = DLE;
361 *ptr++ = ETX;
362
363 l = ptr-pkt;
364
365 send_to_tty(garmin_data_p->port, pkt, l);
366 return 0;
367 }
368
369
370
371 /*
372 * called for a complete packet received from tty layer
373 *
374 * the complete packet (pktid ... cksum) is in garmin_data_p->inbuf starting
375 * at GSP_INITIAL_OFFSET.
376 *
377 * count - number of bytes in the input buffer including space reserved for
378 * the usb header: GSP_INITIAL_OFFSET + number of bytes in packet
379 * (including pkt-id, data-length a. cksum)
380 */
gsp_rec_packet(struct garmin_data *garmin_data_p, int count)381 static int gsp_rec_packet(struct garmin_data *garmin_data_p, int count)
382 {
383 struct device *dev = &garmin_data_p->port->dev;
384 unsigned long flags;
385 const __u8 *recpkt = garmin_data_p->inbuffer+GSP_INITIAL_OFFSET;
386 __le32 *usbdata = (__le32 *) garmin_data_p->inbuffer;
387 int cksum = 0;
388 int n = 0;
389 int pktid = recpkt[0];
390 int size = recpkt[1];
391
392 usb_serial_debug_data(&garmin_data_p->port->dev, __func__,
393 count-GSP_INITIAL_OFFSET, recpkt);
394
395 if (size != (count-GSP_INITIAL_OFFSET-3)) {
396 dev_dbg(dev, "%s - invalid size, expected %d bytes, got %d\n",
397 __func__, size, (count-GSP_INITIAL_OFFSET-3));
398 return -EINVPKT;
399 }
400
401 cksum += *recpkt++;
402 cksum += *recpkt++;
403
404 /* sanity check, remove after test ... */
405 if ((__u8 *)&(usbdata[3]) != recpkt) {
406 dev_dbg(dev, "%s - ptr mismatch %p - %p\n", __func__,
407 &(usbdata[4]), recpkt);
408 return -EINVPKT;
409 }
410
411 while (n < size) {
412 cksum += *recpkt++;
413 n++;
414 }
415
416 if (((cksum + *recpkt) & 0xff) != 0) {
417 dev_dbg(dev, "%s - invalid checksum, expected %02x, got %02x\n",
418 __func__, -cksum & 0xff, *recpkt);
419 return -EINVPKT;
420 }
421
422 usbdata[0] = __cpu_to_le32(GARMIN_LAYERID_APPL);
423 usbdata[1] = __cpu_to_le32(pktid);
424 usbdata[2] = __cpu_to_le32(size);
425
426 garmin_write_bulk(garmin_data_p->port, garmin_data_p->inbuffer,
427 GARMIN_PKTHDR_LENGTH+size, 0);
428
429 /* if this was an abort-transfer command, flush all
430 queued data. */
431 if (isAbortTrfCmnd(garmin_data_p->inbuffer)) {
432 spin_lock_irqsave(&garmin_data_p->lock, flags);
433 garmin_data_p->flags |= FLAGS_DROP_DATA;
434 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
435 pkt_clear(garmin_data_p);
436 }
437
438 return count;
439 }
440
441
442
443 /*
444 * Called for data received from tty
445 *
446 * buf contains the data read, it may span more than one packet or even
447 * incomplete packets
448 *
449 * input record should be a serial-record, but it may not be complete.
450 * Copy it into our local buffer, until an etx is seen (or an error
451 * occurs).
452 * Once the record is complete, convert into a usb packet and send it
453 * to the bulk pipe, send an ack back to the tty.
454 *
455 * If the input is an ack, just send the last queued packet to the
456 * tty layer.
457 *
458 * if the input is an abort command, drop all queued data.
459 */
460
gsp_receive(struct garmin_data *garmin_data_p, const unsigned char *buf, int count)461 static int gsp_receive(struct garmin_data *garmin_data_p,
462 const unsigned char *buf, int count)
463 {
464 struct device *dev = &garmin_data_p->port->dev;
465 unsigned long flags;
466 int offs = 0;
467 int ack_or_nak_seen = 0;
468 __u8 *dest;
469 int size;
470 /* dleSeen: set if last byte read was a DLE */
471 int dleSeen;
472 /* skip: if set, skip incoming data until possible start of
473 * new packet
474 */
475 int skip;
476 __u8 data;
477
478 spin_lock_irqsave(&garmin_data_p->lock, flags);
479 dest = garmin_data_p->inbuffer;
480 size = garmin_data_p->insize;
481 dleSeen = garmin_data_p->flags & FLAGS_GSP_DLESEEN;
482 skip = garmin_data_p->flags & FLAGS_GSP_SKIP;
483 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
484
485 /* dev_dbg(dev, "%s - dle=%d skip=%d size=%d count=%d\n",
486 __func__, dleSeen, skip, size, count); */
487
488 if (size == 0)
489 size = GSP_INITIAL_OFFSET;
490
491 while (offs < count) {
492
493 data = *(buf+offs);
494 offs++;
495
496 if (data == DLE) {
497 if (skip) { /* start of a new pkt */
498 skip = 0;
499 size = GSP_INITIAL_OFFSET;
500 dleSeen = 1;
501 } else if (dleSeen) {
502 dest[size++] = data;
503 dleSeen = 0;
504 } else {
505 dleSeen = 1;
506 }
507 } else if (data == ETX) {
508 if (dleSeen) {
509 /* packet complete */
510
511 data = dest[GSP_INITIAL_OFFSET];
512
513 if (data == ACK) {
514 ack_or_nak_seen = ACK;
515 dev_dbg(dev, "ACK packet complete.\n");
516 } else if (data == NAK) {
517 ack_or_nak_seen = NAK;
518 dev_dbg(dev, "NAK packet complete.\n");
519 } else {
520 dev_dbg(dev, "packet complete - id=0x%X.\n",
521 data);
522 gsp_rec_packet(garmin_data_p, size);
523 }
524
525 skip = 1;
526 size = GSP_INITIAL_OFFSET;
527 dleSeen = 0;
528 } else {
529 dest[size++] = data;
530 }
531 } else if (!skip) {
532
533 if (dleSeen) {
534 size = GSP_INITIAL_OFFSET;
535 dleSeen = 0;
536 }
537
538 dest[size++] = data;
539 }
540
541 if (size >= GPS_IN_BUFSIZ) {
542 dev_dbg(dev, "%s - packet too large.\n", __func__);
543 skip = 1;
544 size = GSP_INITIAL_OFFSET;
545 dleSeen = 0;
546 }
547 }
548
549 spin_lock_irqsave(&garmin_data_p->lock, flags);
550
551 garmin_data_p->insize = size;
552
553 /* copy flags back to structure */
554 if (skip)
555 garmin_data_p->flags |= FLAGS_GSP_SKIP;
556 else
557 garmin_data_p->flags &= ~FLAGS_GSP_SKIP;
558
559 if (dleSeen)
560 garmin_data_p->flags |= FLAGS_GSP_DLESEEN;
561 else
562 garmin_data_p->flags &= ~FLAGS_GSP_DLESEEN;
563
564 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
565
566 if (ack_or_nak_seen) {
567 if (gsp_next_packet(garmin_data_p) > 0)
568 garmin_data_p->state = STATE_ACTIVE;
569 else
570 garmin_data_p->state = STATE_GSP_WAIT_DATA;
571 }
572 return count;
573 }
574
575
576
577 /*
578 * Sends a usb packet to the tty
579 *
580 * Assumes, that all packages and at an usb-packet boundary.
581 *
582 * return <0 on error, 0 if packet is incomplete or > 0 if packet was sent
583 */
gsp_send(struct garmin_data *garmin_data_p, const unsigned char *buf, int count)584 static int gsp_send(struct garmin_data *garmin_data_p,
585 const unsigned char *buf, int count)
586 {
587 struct device *dev = &garmin_data_p->port->dev;
588 const unsigned char *src;
589 unsigned char *dst;
590 int pktid = 0;
591 int datalen = 0;
592 int cksum = 0;
593 int i = 0;
594 int k;
595
596 dev_dbg(dev, "%s - state %d - %d bytes.\n", __func__,
597 garmin_data_p->state, count);
598
599 k = garmin_data_p->outsize;
600 if ((k+count) > GPS_OUT_BUFSIZ) {
601 dev_dbg(dev, "packet too large\n");
602 garmin_data_p->outsize = 0;
603 return -4;
604 }
605
606 memcpy(garmin_data_p->outbuffer+k, buf, count);
607 k += count;
608 garmin_data_p->outsize = k;
609
610 if (k >= GARMIN_PKTHDR_LENGTH) {
611 pktid = getPacketId(garmin_data_p->outbuffer);
612 datalen = getDataLength(garmin_data_p->outbuffer);
613 i = GARMIN_PKTHDR_LENGTH + datalen;
614 if (k < i)
615 return 0;
616 } else {
617 return 0;
618 }
619
620 dev_dbg(dev, "%s - %d bytes in buffer, %d bytes in pkt.\n", __func__, k, i);
621
622 /* garmin_data_p->outbuffer now contains a complete packet */
623
624 usb_serial_debug_data(&garmin_data_p->port->dev, __func__, k,
625 garmin_data_p->outbuffer);
626
627 garmin_data_p->outsize = 0;
628
629 if (getLayerId(garmin_data_p->outbuffer) != GARMIN_LAYERID_APPL) {
630 dev_dbg(dev, "not an application packet (%d)\n",
631 getLayerId(garmin_data_p->outbuffer));
632 return -1;
633 }
634
635 if (pktid > 255) {
636 dev_dbg(dev, "packet-id %d too large\n", pktid);
637 return -2;
638 }
639
640 if (datalen > 255) {
641 dev_dbg(dev, "packet-size %d too large\n", datalen);
642 return -3;
643 }
644
645 /* the serial protocol should be able to handle this packet */
646
647 k = 0;
648 src = garmin_data_p->outbuffer+GARMIN_PKTHDR_LENGTH;
649 for (i = 0; i < datalen; i++) {
650 if (*src++ == DLE)
651 k++;
652 }
653
654 src = garmin_data_p->outbuffer+GARMIN_PKTHDR_LENGTH;
655 if (k > (GARMIN_PKTHDR_LENGTH-2)) {
656 /* can't add stuffing DLEs in place, move data to end
657 of buffer ... */
658 dst = garmin_data_p->outbuffer+GPS_OUT_BUFSIZ-datalen;
659 memcpy(dst, src, datalen);
660 src = dst;
661 }
662
663 dst = garmin_data_p->outbuffer;
664
665 *dst++ = DLE;
666 *dst++ = pktid;
667 cksum += pktid;
668 *dst++ = datalen;
669 cksum += datalen;
670 if (datalen == DLE)
671 *dst++ = DLE;
672
673 for (i = 0; i < datalen; i++) {
674 __u8 c = *src++;
675 *dst++ = c;
676 cksum += c;
677 if (c == DLE)
678 *dst++ = DLE;
679 }
680
681 cksum = -cksum & 0xFF;
682 *dst++ = cksum;
683 if (cksum == DLE)
684 *dst++ = DLE;
685 *dst++ = DLE;
686 *dst++ = ETX;
687
688 i = dst-garmin_data_p->outbuffer;
689
690 send_to_tty(garmin_data_p->port, garmin_data_p->outbuffer, i);
691
692 garmin_data_p->pkt_id = pktid;
693 garmin_data_p->state = STATE_WAIT_TTY_ACK;
694
695 return i;
696 }
697
698
699 /*
700 * Process the next pending data packet - if there is one
701 */
gsp_next_packet(struct garmin_data *garmin_data_p)702 static int gsp_next_packet(struct garmin_data *garmin_data_p)
703 {
704 int result = 0;
705 struct garmin_packet *pkt = NULL;
706
707 while ((pkt = pkt_pop(garmin_data_p)) != NULL) {
708 dev_dbg(&garmin_data_p->port->dev, "%s - next pkt: %d\n", __func__, pkt->seq);
709 result = gsp_send(garmin_data_p, pkt->data, pkt->size);
710 if (result > 0) {
711 kfree(pkt);
712 return result;
713 }
714 kfree(pkt);
715 }
716 return result;
717 }
718
719
720
721 /******************************************************************************
722 * garmin native mode
723 ******************************************************************************/
724
725
726 /*
727 * Called for data received from tty
728 *
729 * The input data is expected to be in garmin usb-packet format.
730 *
731 * buf contains the data read, it may span more than one packet
732 * or even incomplete packets
733 */
nat_receive(struct garmin_data *garmin_data_p, const unsigned char *buf, int count)734 static int nat_receive(struct garmin_data *garmin_data_p,
735 const unsigned char *buf, int count)
736 {
737 unsigned long flags;
738 __u8 *dest;
739 int offs = 0;
740 int result = count;
741 int len;
742
743 while (offs < count) {
744 /* if buffer contains header, copy rest of data */
745 if (garmin_data_p->insize >= GARMIN_PKTHDR_LENGTH)
746 len = GARMIN_PKTHDR_LENGTH
747 +getDataLength(garmin_data_p->inbuffer);
748 else
749 len = GARMIN_PKTHDR_LENGTH;
750
751 if (len >= GPS_IN_BUFSIZ) {
752 /* seems to be an invalid packet, ignore rest
753 of input */
754 dev_dbg(&garmin_data_p->port->dev,
755 "%s - packet size too large: %d\n",
756 __func__, len);
757 garmin_data_p->insize = 0;
758 count = 0;
759 result = -EINVPKT;
760 } else {
761 len -= garmin_data_p->insize;
762 if (len > (count-offs))
763 len = (count-offs);
764 if (len > 0) {
765 dest = garmin_data_p->inbuffer
766 + garmin_data_p->insize;
767 memcpy(dest, buf+offs, len);
768 garmin_data_p->insize += len;
769 offs += len;
770 }
771 }
772
773 /* do we have a complete packet ? */
774 if (garmin_data_p->insize >= GARMIN_PKTHDR_LENGTH) {
775 len = GARMIN_PKTHDR_LENGTH+
776 getDataLength(garmin_data_p->inbuffer);
777 if (garmin_data_p->insize >= len) {
778 garmin_write_bulk(garmin_data_p->port,
779 garmin_data_p->inbuffer,
780 len, 0);
781 garmin_data_p->insize = 0;
782
783 /* if this was an abort-transfer command,
784 flush all queued data. */
785 if (isAbortTrfCmnd(garmin_data_p->inbuffer)) {
786 spin_lock_irqsave(&garmin_data_p->lock,
787 flags);
788 garmin_data_p->flags |= FLAGS_DROP_DATA;
789 spin_unlock_irqrestore(
790 &garmin_data_p->lock, flags);
791 pkt_clear(garmin_data_p);
792 }
793 }
794 }
795 }
796 return result;
797 }
798
799
800 /******************************************************************************
801 * private packets
802 ******************************************************************************/
803
priv_status_resp(struct usb_serial_port *port)804 static void priv_status_resp(struct usb_serial_port *port)
805 {
806 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
807 __le32 *pkt = (__le32 *)garmin_data_p->privpkt;
808
809 pkt[0] = __cpu_to_le32(GARMIN_LAYERID_PRIVATE);
810 pkt[1] = __cpu_to_le32(PRIV_PKTID_INFO_RESP);
811 pkt[2] = __cpu_to_le32(12);
812 pkt[3] = __cpu_to_le32(VERSION_MAJOR << 16 | VERSION_MINOR);
813 pkt[4] = __cpu_to_le32(garmin_data_p->mode);
814 pkt[5] = __cpu_to_le32(garmin_data_p->serial_num);
815
816 send_to_tty(port, (__u8 *)pkt, 6 * 4);
817 }
818
819
820 /******************************************************************************
821 * Garmin specific driver functions
822 ******************************************************************************/
823
process_resetdev_request(struct usb_serial_port *port)824 static int process_resetdev_request(struct usb_serial_port *port)
825 {
826 unsigned long flags;
827 int status;
828 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
829
830 spin_lock_irqsave(&garmin_data_p->lock, flags);
831 garmin_data_p->flags &= ~(CLEAR_HALT_REQUIRED);
832 garmin_data_p->state = STATE_RESET;
833 garmin_data_p->serial_num = 0;
834 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
835
836 usb_kill_urb(port->interrupt_in_urb);
837 dev_dbg(&port->dev, "%s - usb_reset_device\n", __func__);
838 status = usb_reset_device(port->serial->dev);
839 if (status)
840 dev_dbg(&port->dev, "%s - usb_reset_device failed: %d\n",
841 __func__, status);
842 return status;
843 }
844
845
846
847 /*
848 * clear all cached data
849 */
garmin_clear(struct garmin_data *garmin_data_p)850 static int garmin_clear(struct garmin_data *garmin_data_p)
851 {
852 unsigned long flags;
853
854 /* flush all queued data */
855 pkt_clear(garmin_data_p);
856
857 spin_lock_irqsave(&garmin_data_p->lock, flags);
858 garmin_data_p->insize = 0;
859 garmin_data_p->outsize = 0;
860 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
861
862 return 0;
863 }
864
865
garmin_init_session(struct usb_serial_port *port)866 static int garmin_init_session(struct usb_serial_port *port)
867 {
868 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
869 int status;
870 int i;
871
872 usb_kill_urb(port->interrupt_in_urb);
873
874 status = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
875 if (status) {
876 dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
877 status);
878 return status;
879 }
880
881 /*
882 * using the initialization method from gpsbabel. See comments in
883 * gpsbabel/jeeps/gpslibusb.c gusb_reset_toggles()
884 */
885 dev_dbg(&port->dev, "%s - starting session ...\n", __func__);
886 garmin_data_p->state = STATE_ACTIVE;
887
888 for (i = 0; i < 3; i++) {
889 status = garmin_write_bulk(port, GARMIN_START_SESSION_REQ,
890 sizeof(GARMIN_START_SESSION_REQ), 0);
891 if (status < 0)
892 goto err_kill_urbs;
893 }
894
895 return 0;
896
897 err_kill_urbs:
898 usb_kill_anchored_urbs(&garmin_data_p->write_urbs);
899 usb_kill_urb(port->interrupt_in_urb);
900
901 return status;
902 }
903
904
905
garmin_open(struct tty_struct *tty, struct usb_serial_port *port)906 static int garmin_open(struct tty_struct *tty, struct usb_serial_port *port)
907 {
908 unsigned long flags;
909 int status = 0;
910 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
911
912 spin_lock_irqsave(&garmin_data_p->lock, flags);
913 garmin_data_p->mode = initial_mode;
914 garmin_data_p->count = 0;
915 garmin_data_p->flags &= FLAGS_SESSION_REPLY1_SEEN;
916 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
917
918 /* shutdown any bulk reads that might be going on */
919 usb_kill_urb(port->read_urb);
920
921 if (garmin_data_p->state == STATE_RESET)
922 status = garmin_init_session(port);
923
924 garmin_data_p->state = STATE_ACTIVE;
925 return status;
926 }
927
928
garmin_close(struct usb_serial_port *port)929 static void garmin_close(struct usb_serial_port *port)
930 {
931 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
932
933 dev_dbg(&port->dev, "%s - mode=%d state=%d flags=0x%X\n",
934 __func__, garmin_data_p->mode, garmin_data_p->state,
935 garmin_data_p->flags);
936
937 garmin_clear(garmin_data_p);
938
939 /* shutdown our urbs */
940 usb_kill_urb(port->read_urb);
941 usb_kill_anchored_urbs(&garmin_data_p->write_urbs);
942
943 /* keep reset state so we know that we must start a new session */
944 if (garmin_data_p->state != STATE_RESET)
945 garmin_data_p->state = STATE_DISCONNECTED;
946 }
947
948
garmin_write_bulk_callback(struct urb *urb)949 static void garmin_write_bulk_callback(struct urb *urb)
950 {
951 struct usb_serial_port *port = urb->context;
952
953 if (port) {
954 struct garmin_data *garmin_data_p =
955 usb_get_serial_port_data(port);
956
957 if (getLayerId(urb->transfer_buffer) == GARMIN_LAYERID_APPL) {
958
959 if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
960 gsp_send_ack(garmin_data_p,
961 ((__u8 *)urb->transfer_buffer)[4]);
962 }
963 }
964 usb_serial_port_softint(port);
965 }
966
967 /* Ignore errors that resulted from garmin_write_bulk with
968 dismiss_ack = 1 */
969
970 /* free up the transfer buffer, as usb_free_urb() does not do this */
971 kfree(urb->transfer_buffer);
972 }
973
974
garmin_write_bulk(struct usb_serial_port *port, const unsigned char *buf, int count, int dismiss_ack)975 static int garmin_write_bulk(struct usb_serial_port *port,
976 const unsigned char *buf, int count,
977 int dismiss_ack)
978 {
979 unsigned long flags;
980 struct usb_serial *serial = port->serial;
981 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
982 struct urb *urb;
983 unsigned char *buffer;
984 int status;
985
986 spin_lock_irqsave(&garmin_data_p->lock, flags);
987 garmin_data_p->flags &= ~FLAGS_DROP_DATA;
988 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
989
990 buffer = kmalloc(count, GFP_ATOMIC);
991 if (!buffer)
992 return -ENOMEM;
993
994 urb = usb_alloc_urb(0, GFP_ATOMIC);
995 if (!urb) {
996 kfree(buffer);
997 return -ENOMEM;
998 }
999
1000 memcpy(buffer, buf, count);
1001
1002 usb_serial_debug_data(&port->dev, __func__, count, buffer);
1003
1004 usb_fill_bulk_urb(urb, serial->dev,
1005 usb_sndbulkpipe(serial->dev,
1006 port->bulk_out_endpointAddress),
1007 buffer, count,
1008 garmin_write_bulk_callback,
1009 dismiss_ack ? NULL : port);
1010 urb->transfer_flags |= URB_ZERO_PACKET;
1011
1012 if (getLayerId(buffer) == GARMIN_LAYERID_APPL) {
1013
1014 spin_lock_irqsave(&garmin_data_p->lock, flags);
1015 garmin_data_p->flags |= APP_REQ_SEEN;
1016 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1017
1018 if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1019 pkt_clear(garmin_data_p);
1020 garmin_data_p->state = STATE_GSP_WAIT_DATA;
1021 }
1022 }
1023
1024 /* send it down the pipe */
1025 usb_anchor_urb(urb, &garmin_data_p->write_urbs);
1026 status = usb_submit_urb(urb, GFP_ATOMIC);
1027 if (status) {
1028 dev_err(&port->dev,
1029 "%s - usb_submit_urb(write bulk) failed with status = %d\n",
1030 __func__, status);
1031 count = status;
1032 usb_unanchor_urb(urb);
1033 kfree(buffer);
1034 }
1035
1036 /* we are done with this urb, so let the host driver
1037 * really free it when it is finished with it */
1038 usb_free_urb(urb);
1039
1040 return count;
1041 }
1042
garmin_write(struct tty_struct *tty, struct usb_serial_port *port, const unsigned char *buf, int count)1043 static int garmin_write(struct tty_struct *tty, struct usb_serial_port *port,
1044 const unsigned char *buf, int count)
1045 {
1046 struct device *dev = &port->dev;
1047 int pktid, pktsiz, len;
1048 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1049 __le32 *privpkt = (__le32 *)garmin_data_p->privpkt;
1050
1051 usb_serial_debug_data(dev, __func__, count, buf);
1052
1053 if (garmin_data_p->state == STATE_RESET)
1054 return -EIO;
1055
1056 /* check for our private packets */
1057 if (count >= GARMIN_PKTHDR_LENGTH) {
1058 len = PRIVPKTSIZ;
1059 if (count < len)
1060 len = count;
1061
1062 memcpy(garmin_data_p->privpkt, buf, len);
1063
1064 pktsiz = getDataLength(garmin_data_p->privpkt);
1065 pktid = getPacketId(garmin_data_p->privpkt);
1066
1067 if (count == (GARMIN_PKTHDR_LENGTH + pktsiz) &&
1068 getLayerId(garmin_data_p->privpkt) ==
1069 GARMIN_LAYERID_PRIVATE) {
1070
1071 dev_dbg(dev, "%s - processing private request %d\n",
1072 __func__, pktid);
1073
1074 /* drop all unfinished transfers */
1075 garmin_clear(garmin_data_p);
1076
1077 switch (pktid) {
1078 case PRIV_PKTID_SET_MODE:
1079 if (pktsiz != 4)
1080 return -EINVPKT;
1081 garmin_data_p->mode = __le32_to_cpu(privpkt[3]);
1082 dev_dbg(dev, "%s - mode set to %d\n",
1083 __func__, garmin_data_p->mode);
1084 break;
1085
1086 case PRIV_PKTID_INFO_REQ:
1087 priv_status_resp(port);
1088 break;
1089
1090 case PRIV_PKTID_RESET_REQ:
1091 process_resetdev_request(port);
1092 break;
1093
1094 case PRIV_PKTID_SET_DEF_MODE:
1095 if (pktsiz != 4)
1096 return -EINVPKT;
1097 initial_mode = __le32_to_cpu(privpkt[3]);
1098 dev_dbg(dev, "%s - initial_mode set to %d\n",
1099 __func__,
1100 garmin_data_p->mode);
1101 break;
1102 }
1103 return count;
1104 }
1105 }
1106
1107 if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1108 return gsp_receive(garmin_data_p, buf, count);
1109 } else { /* MODE_NATIVE */
1110 return nat_receive(garmin_data_p, buf, count);
1111 }
1112 }
1113
1114
garmin_write_room(struct tty_struct *tty)1115 static int garmin_write_room(struct tty_struct *tty)
1116 {
1117 struct usb_serial_port *port = tty->driver_data;
1118 /*
1119 * Report back the bytes currently available in the output buffer.
1120 */
1121 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1122 return GPS_OUT_BUFSIZ-garmin_data_p->outsize;
1123 }
1124
1125
garmin_read_process(struct garmin_data *garmin_data_p, unsigned char *data, unsigned data_length, int bulk_data)1126 static void garmin_read_process(struct garmin_data *garmin_data_p,
1127 unsigned char *data, unsigned data_length,
1128 int bulk_data)
1129 {
1130 unsigned long flags;
1131
1132 if (garmin_data_p->flags & FLAGS_DROP_DATA) {
1133 /* abort-transfer cmd is active */
1134 dev_dbg(&garmin_data_p->port->dev, "%s - pkt dropped\n", __func__);
1135 } else if (garmin_data_p->state != STATE_DISCONNECTED &&
1136 garmin_data_p->state != STATE_RESET) {
1137
1138 /* if throttling is active or postprecessing is required
1139 put the received data in the input queue, otherwise
1140 send it directly to the tty port */
1141 if (garmin_data_p->flags & FLAGS_QUEUING) {
1142 pkt_add(garmin_data_p, data, data_length);
1143 } else if (bulk_data || (data_length >= sizeof(u32) &&
1144 getLayerId(data) == GARMIN_LAYERID_APPL)) {
1145
1146 spin_lock_irqsave(&garmin_data_p->lock, flags);
1147 garmin_data_p->flags |= APP_RESP_SEEN;
1148 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1149
1150 if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1151 pkt_add(garmin_data_p, data, data_length);
1152 } else {
1153 send_to_tty(garmin_data_p->port, data,
1154 data_length);
1155 }
1156 }
1157 /* ignore system layer packets ... */
1158 }
1159 }
1160
1161
garmin_read_bulk_callback(struct urb *urb)1162 static void garmin_read_bulk_callback(struct urb *urb)
1163 {
1164 unsigned long flags;
1165 struct usb_serial_port *port = urb->context;
1166 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1167 unsigned char *data = urb->transfer_buffer;
1168 int status = urb->status;
1169 int retval;
1170
1171 if (status) {
1172 dev_dbg(&urb->dev->dev, "%s - nonzero read bulk status received: %d\n",
1173 __func__, status);
1174 return;
1175 }
1176
1177 usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1178
1179 garmin_read_process(garmin_data_p, data, urb->actual_length, 1);
1180
1181 if (urb->actual_length == 0 &&
1182 (garmin_data_p->flags & FLAGS_BULK_IN_RESTART) != 0) {
1183 spin_lock_irqsave(&garmin_data_p->lock, flags);
1184 garmin_data_p->flags &= ~FLAGS_BULK_IN_RESTART;
1185 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1186 retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1187 if (retval)
1188 dev_err(&port->dev,
1189 "%s - failed resubmitting read urb, error %d\n",
1190 __func__, retval);
1191 } else if (urb->actual_length > 0) {
1192 /* Continue trying to read until nothing more is received */
1193 if ((garmin_data_p->flags & FLAGS_THROTTLED) == 0) {
1194 retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1195 if (retval)
1196 dev_err(&port->dev,
1197 "%s - failed resubmitting read urb, error %d\n",
1198 __func__, retval);
1199 }
1200 } else {
1201 dev_dbg(&port->dev, "%s - end of bulk data\n", __func__);
1202 spin_lock_irqsave(&garmin_data_p->lock, flags);
1203 garmin_data_p->flags &= ~FLAGS_BULK_IN_ACTIVE;
1204 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1205 }
1206 }
1207
1208
garmin_read_int_callback(struct urb *urb)1209 static void garmin_read_int_callback(struct urb *urb)
1210 {
1211 unsigned long flags;
1212 int retval;
1213 struct usb_serial_port *port = urb->context;
1214 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1215 unsigned char *data = urb->transfer_buffer;
1216 int status = urb->status;
1217
1218 switch (status) {
1219 case 0:
1220 /* success */
1221 break;
1222 case -ECONNRESET:
1223 case -ENOENT:
1224 case -ESHUTDOWN:
1225 /* this urb is terminated, clean up */
1226 dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d\n",
1227 __func__, status);
1228 return;
1229 default:
1230 dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n",
1231 __func__, status);
1232 return;
1233 }
1234
1235 usb_serial_debug_data(&port->dev, __func__, urb->actual_length,
1236 urb->transfer_buffer);
1237
1238 if (urb->actual_length == sizeof(GARMIN_BULK_IN_AVAIL_REPLY) &&
1239 memcmp(data, GARMIN_BULK_IN_AVAIL_REPLY,
1240 sizeof(GARMIN_BULK_IN_AVAIL_REPLY)) == 0) {
1241
1242 dev_dbg(&port->dev, "%s - bulk data available.\n", __func__);
1243
1244 if ((garmin_data_p->flags & FLAGS_BULK_IN_ACTIVE) == 0) {
1245
1246 /* bulk data available */
1247 retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1248 if (retval) {
1249 dev_err(&port->dev,
1250 "%s - failed submitting read urb, error %d\n",
1251 __func__, retval);
1252 } else {
1253 spin_lock_irqsave(&garmin_data_p->lock, flags);
1254 garmin_data_p->flags |= FLAGS_BULK_IN_ACTIVE;
1255 spin_unlock_irqrestore(&garmin_data_p->lock,
1256 flags);
1257 }
1258 } else {
1259 /* bulk-in transfer still active */
1260 spin_lock_irqsave(&garmin_data_p->lock, flags);
1261 garmin_data_p->flags |= FLAGS_BULK_IN_RESTART;
1262 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1263 }
1264
1265 } else if (urb->actual_length == (4+sizeof(GARMIN_START_SESSION_REPLY))
1266 && memcmp(data, GARMIN_START_SESSION_REPLY,
1267 sizeof(GARMIN_START_SESSION_REPLY)) == 0) {
1268
1269 spin_lock_irqsave(&garmin_data_p->lock, flags);
1270 garmin_data_p->flags |= FLAGS_SESSION_REPLY1_SEEN;
1271 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1272
1273 /* save the serial number */
1274 garmin_data_p->serial_num = __le32_to_cpup(
1275 (__le32 *)(data+GARMIN_PKTHDR_LENGTH));
1276
1277 dev_dbg(&port->dev, "%s - start-of-session reply seen - serial %u.\n",
1278 __func__, garmin_data_p->serial_num);
1279 }
1280
1281 garmin_read_process(garmin_data_p, data, urb->actual_length, 0);
1282
1283 retval = usb_submit_urb(urb, GFP_ATOMIC);
1284 if (retval)
1285 dev_err(&urb->dev->dev,
1286 "%s - Error %d submitting interrupt urb\n",
1287 __func__, retval);
1288 }
1289
1290
1291 /*
1292 * Sends the next queued packt to the tty port (garmin native mode only)
1293 * and then sets a timer to call itself again until all queued data
1294 * is sent.
1295 */
garmin_flush_queue(struct garmin_data *garmin_data_p)1296 static int garmin_flush_queue(struct garmin_data *garmin_data_p)
1297 {
1298 unsigned long flags;
1299 struct garmin_packet *pkt;
1300
1301 if ((garmin_data_p->flags & FLAGS_THROTTLED) == 0) {
1302 pkt = pkt_pop(garmin_data_p);
1303 if (pkt != NULL) {
1304 send_to_tty(garmin_data_p->port, pkt->data, pkt->size);
1305 kfree(pkt);
1306 mod_timer(&garmin_data_p->timer, (1)+jiffies);
1307
1308 } else {
1309 spin_lock_irqsave(&garmin_data_p->lock, flags);
1310 garmin_data_p->flags &= ~FLAGS_QUEUING;
1311 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1312 }
1313 }
1314 return 0;
1315 }
1316
1317
garmin_throttle(struct tty_struct *tty)1318 static void garmin_throttle(struct tty_struct *tty)
1319 {
1320 struct usb_serial_port *port = tty->driver_data;
1321 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1322
1323 /* set flag, data received will be put into a queue
1324 for later processing */
1325 spin_lock_irq(&garmin_data_p->lock);
1326 garmin_data_p->flags |= FLAGS_QUEUING|FLAGS_THROTTLED;
1327 spin_unlock_irq(&garmin_data_p->lock);
1328 }
1329
1330
garmin_unthrottle(struct tty_struct *tty)1331 static void garmin_unthrottle(struct tty_struct *tty)
1332 {
1333 struct usb_serial_port *port = tty->driver_data;
1334 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1335 int status;
1336
1337 spin_lock_irq(&garmin_data_p->lock);
1338 garmin_data_p->flags &= ~FLAGS_THROTTLED;
1339 spin_unlock_irq(&garmin_data_p->lock);
1340
1341 /* in native mode send queued data to tty, in
1342 serial mode nothing needs to be done here */
1343 if (garmin_data_p->mode == MODE_NATIVE)
1344 garmin_flush_queue(garmin_data_p);
1345
1346 if ((garmin_data_p->flags & FLAGS_BULK_IN_ACTIVE) != 0) {
1347 status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1348 if (status)
1349 dev_err(&port->dev,
1350 "%s - failed resubmitting read urb, error %d\n",
1351 __func__, status);
1352 }
1353 }
1354
1355 /*
1356 * The timer is currently only used to send queued packets to
1357 * the tty in cases where the protocol provides no own handshaking
1358 * to initiate the transfer.
1359 */
timeout_handler(struct timer_list *t)1360 static void timeout_handler(struct timer_list *t)
1361 {
1362 struct garmin_data *garmin_data_p = from_timer(garmin_data_p, t, timer);
1363
1364 /* send the next queued packet to the tty port */
1365 if (garmin_data_p->mode == MODE_NATIVE)
1366 if (garmin_data_p->flags & FLAGS_QUEUING)
1367 garmin_flush_queue(garmin_data_p);
1368 }
1369
1370
1371
garmin_port_probe(struct usb_serial_port *port)1372 static int garmin_port_probe(struct usb_serial_port *port)
1373 {
1374 int status;
1375 struct garmin_data *garmin_data_p;
1376
1377 garmin_data_p = kzalloc(sizeof(struct garmin_data), GFP_KERNEL);
1378 if (!garmin_data_p)
1379 return -ENOMEM;
1380
1381 timer_setup(&garmin_data_p->timer, timeout_handler, 0);
1382 spin_lock_init(&garmin_data_p->lock);
1383 INIT_LIST_HEAD(&garmin_data_p->pktlist);
1384 garmin_data_p->port = port;
1385 garmin_data_p->state = 0;
1386 garmin_data_p->flags = 0;
1387 garmin_data_p->count = 0;
1388 init_usb_anchor(&garmin_data_p->write_urbs);
1389 usb_set_serial_port_data(port, garmin_data_p);
1390
1391 status = garmin_init_session(port);
1392 if (status)
1393 goto err_free;
1394
1395 return 0;
1396 err_free:
1397 kfree(garmin_data_p);
1398
1399 return status;
1400 }
1401
1402
garmin_port_remove(struct usb_serial_port *port)1403 static int garmin_port_remove(struct usb_serial_port *port)
1404 {
1405 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1406
1407 usb_kill_anchored_urbs(&garmin_data_p->write_urbs);
1408 usb_kill_urb(port->interrupt_in_urb);
1409 del_timer_sync(&garmin_data_p->timer);
1410 kfree(garmin_data_p);
1411 return 0;
1412 }
1413
1414
1415 /* All of the device info needed */
1416 static struct usb_serial_driver garmin_device = {
1417 .driver = {
1418 .owner = THIS_MODULE,
1419 .name = "garmin_gps",
1420 },
1421 .description = "Garmin GPS usb/tty",
1422 .id_table = id_table,
1423 .num_ports = 1,
1424 .open = garmin_open,
1425 .close = garmin_close,
1426 .throttle = garmin_throttle,
1427 .unthrottle = garmin_unthrottle,
1428 .port_probe = garmin_port_probe,
1429 .port_remove = garmin_port_remove,
1430 .write = garmin_write,
1431 .write_room = garmin_write_room,
1432 .write_bulk_callback = garmin_write_bulk_callback,
1433 .read_bulk_callback = garmin_read_bulk_callback,
1434 .read_int_callback = garmin_read_int_callback,
1435 };
1436
1437 static struct usb_serial_driver * const serial_drivers[] = {
1438 &garmin_device, NULL
1439 };
1440
1441 module_usb_serial_driver(serial_drivers, id_table);
1442
1443 MODULE_AUTHOR(DRIVER_AUTHOR);
1444 MODULE_DESCRIPTION(DRIVER_DESC);
1445 MODULE_LICENSE("GPL");
1446
1447 module_param(initial_mode, int, S_IRUGO);
1448 MODULE_PARM_DESC(initial_mode, "Initial mode");
1449